file-watcher

I use a File Watcher defined as this Here is my watchers.xml file: <?xml version="1.0" encoding="UTF-8"?> <TaskOptions> <TaskOptions> <option name="arguments" value="fix $FileDir$/$FileName$ --verbose " /> <option name="checkSyntaxErrors" value="false" /> <option name="description" /> <option name="exitCodeBehavior" value="ERROR" /> <option name="fileExtension" value="php" /> <option name="immediateSync" value="true" /> <option name="name" value="PHP CS Fixer" /> <option name="output" value="" /> <option name="outputFilters"> <array /> </option> <option name="outputFromStdout" value="false" />

I want to watch a folder with powershell and I am a PS beginner. That script works ONE time when I start the script. But when I have to restart the script again because I changed some script code I get this error message: Cannot subscribe to the specified event. A subscriber with the source identifier 'FileChanged' already exists. I tried: this at the top of the script: Unregister-Event -SourceIdentifier FileChanged does not work. How do I correctly unregister the event so I can run my script as often I want and the previously registered event is disposed? CODE $folder = "C:\temp" $Watcher =

Can I have file watcher on HDFS ? Scenario: The files are landing on HDFS continuously.I want to start a Spark Job once the number of files reached a threshold(it can be number of files or size of the files). Is it possible to implement file watcher on HDFS to achieve this . If yes, then can anyone suggest the way to do it?What are the different options available? Can the Zookeeper or the Oozie do it? Any help will be appreciated.Thanks. Hadoop 2.6 introduced DFSInotifyEventInputStream that you can use for this. You can get an instance of it from HdfsAdmin and then just call .take() or .poll()